


A Shadowhunter's Halloween

by Baneofwonderland



Series: Shadowhunting Halloween [2]
Category: Shadowhunters, The Mortal Instruments
Genre: Drama, Fluff, Fun, Grease - Freeform, Halloween Costumes, Halloween fun, Lightwood Siblings, M/M kissing, Malec in an established relationship, Multi, Poor Simon, Really? - Freeform, Star Wars - Freeform, clace happenings, dr who, halloween party, it's fun and fancy free, it's not a crossover just some Halloween costumes, mentions of Sizzy, mentions of malec, party time, some saphael, some smooches, suggestive innuendos
Language: English
Status: Completed
Published: 2016-10-27
Updated: 2016-10-27
Packaged: 2018-08-27 02:05:11
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 7
Words: 4,669
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8383636
Author URL: https://archiveofourown.org/users/Baneofwonderland/pseuds/Baneofwonderland
Summary: Magnus is throwing a Halloween Party to which everyone must attend! But we'll see how things turn out for the hunters who are never technically off duty...





	1. Alec Receives His Invite

**Author's Note:**

  * For [AlyxHavok](https://archiveofourown.org/users/AlyxHavok/gifts).



"I'm not going." Alec tossed the invite onto the kitchen table.

"Yes, you are." Izzy retorted, picking up the discarded invite.

"Iz, it's ridiculous."

Izzy skimmed Alec's personal invitation. The invite had been sitting next to his side of the bed when Alec had woken earlier that day, Magnus being suspiciously up before he was. For good reason it seemed.

Alec had known Magnus was throwing a party for Halloween. He also knew how against the idea Alec had been. Halloween had always just been an excuse for rogue Downworlders to walk amongst mundanes without suspicion. Which was fine except for when they partied a little too hard and a mundane eventually paid the price for it.

"Alec, you have to go. He's your boyfriend and he's going to want you there. Besides..." Izzy fanned herself with the invite. "It looks like you're going to be a part of a couples costume."

Her mocking grin was enough to propel him out of the kitchen and back into the bedroom where Alec unceremoniously kicked the door shut behind him. 

It was stupid. The entire thing. Someone was going to do something uncommonly idiotic and get themselves turned into a bat with pink wings or a snack for a vampire. 

Alec scrubbed a hand down his face.

He really hated Halloween. 

And what the hell was a Han Solo?!


	2. Gearing up for the Festivities

**Summary for the Chapter:**

> Magnus gets a little too into his party planning and suffers a visit from dear Raphael.

Magnus was really just having too much fun. The decorations were pouring in by the hour and Pandemonium had never looked better in his opinion. The entire place oozed 1920s sophistication with a splash of Rocky Horror influence. The colors clashed wonderfully with the decor and it was perfect. Magnus had never felt more impressed by himself. 

" _Dios,_ this place looks horrific." 

Magnus turned toward his surly guest. Raphael was entering through the back alley entrance of the club holding a white envelope in his hands. Magnus glowered at him.

"And I'm to trust the opinion of someone who calls a decrepit, moldy hotel home? Honey, you wouldn't know taste if Martha Stewart gave you a one year course in home decorating."

"Who?" Raphael was only barely paying attention to Magnus, his eyes still jumping from the painted walls to the sequined couches.

"Nevermind.. What do you want Raphael?" Magnus went back to surveying his painting swatches. The back wall needed more pop and he just couldn't decide which color he needed most.

"I didn't understand your invitation." Raphael said slowly, thrusting said invite toward Magnus who barely spared it a glance.

"Whats not to understand?" Magnus held a brilliant orange swatch out in front of himself and squinted. Perhaps that would be a tad much. 

"For one thing, I have no idea what this character is." Raphael responded in apparent disgust. 

Magnus sighed. Did no one else have vision? Did no one else know how to have fun? Did no one understand the importance of a Halloween party?!

"Honestly Raphael... Just throw on a pink jacket and you'll be perfect. Now go. I have things to prepare!"

Magnus waved his hands and a shower of blue sparks fell from them turning the back wall a deep purple. It was just gaudy enough to work. 

Raphael huffed but said nothing as he turned back the way he came. 


	3. Costume Shopping

**Summary for the Chapter:**

> Alec and Izzy discuss their costumes and Alec makes a discovery about his...

There were costumes everywhere. Alec had never seen so many disguises in one location, not even Izzy's closet. He pushed aside a rack that held zombie costumes. Mundanes and their holidays... Alec would never understand them.

"I think I found the closest thing!" Izzy announced, stepping from behind a superhero display. She held up a plastic bag with what was supposed to be her designated costume. Alec had no idea who she was supposed to be. 

"Did you find yours?" Iz asked, eyes flitting down to the bag Alec carried.

"This is the stupidest thing I've ever had to do." Alec scowled down at his costume.

It hadn't taken much convincing from Magnus to get him to agree to the party. In fact, it really had only taken one night in... behind closed doors. 

"I doubt that. Don't worry about it, _mi hermano_. It's gonna be great!" Izzy swung her bag for emphasis nearly knocking over a display with pastel wigs.

"And how cute is it that Magnus picked out a character for each of us to be!" She squealed. 

Alec just rolled his eyes. This party was definitely going to be the death of him.

 

\--

 

Later that night, Alec pulled out the different pieces of his costume from the store bag. Magnus was still out, dealing with some clients on the other end of town so he had time to properly examine the disguise he would dawn over the weekend. He laid out the pants on the bed followed by a sort of tunic shirt, dark vest and an accompanying belt he assumed was for weapons. Alec still wasn't entirely sure who the character was and Izzy hadn't elaborated on what she meant by "couples costume".

He sighed, rubbing the back of his neck. At least he wouldn't be some ridiculous character like Jace. Really, things could have gone a lot worse for him. Alec grabbed his cell off the night stand and opened a search app. At least he still had time to figure out who he was supposed to be. 

He typed out "Han Solo" and "couple" and hit search. The app flooded with news about some space movie and some new reboot he was sure Simon had mentioned awhile back. Apparently his character was someone important. He opened the image search but couldn't bring himself to scroll past the first few images. 

Heat flooded his cheeks in a matter of seconds. 

"Magnusssss....." He groaned.


	4. Green with Dubiousness

**Summary for the Chapter:**

> Magnus and Ragnor prepare for the party festivities. But what a surprise, someone isn't exactly into the idea of having fun.

Magnus had just put the finishing touches on his makeup when a loud crash resounded from Ragnor's kitchen. He rolled his eyes before setting the makeup brush down on the edge of the sink and moving into the hallway. 

"Pea pod?" He teasingly questioned. 

"This blasted cat and this blasted costume and this blasted box are entirely your fault!" Ragnor's shouts were muffled. 

Magnus chuckled as he peeked into the kitchen. His green friend was laying on the floor, one leg caught in the rungs of a kitchen chair, arm covering his face from a white furball. Ragnor's almost perfect costume was now disheveled and his hair was unkempt. It looked as if Chairman Meow had been causing a bit of mischief with Ragnor. Then again, the Chairman was always doing that. 

"Darling, you know the Chairman isn't the biggest fan of green, you really shouldn't startle him." Magnus grinned from the doorway. 

"Then why did you bloody bring him?! And why, pray tell, did you insist on getting ready at my house?" Ragnor roared as he drew himself off the kitchen floor. He glared at Magnus as he tried to straighten out his costume.

"You know Alexander doesn't like Halloween. And he's almost loath to go to any of my wonderful parties. I just wanted something fun for him. And I didn't want to spoil the fun by having him watch me get ready." Magnus leaned in conspiratorially. "He has no idea what I'm going as, y'know." 

Ragnor huffed, straightening his bow tie. 

"And who exactly are you supposed to be? An Egyptian servant?" Ragnor asked, doing a once over of Magnus's costume. 

Magnus adjusted the gold cuff around his upper arm. He was not going to let Ragnor ruin his fun. This costume was something he had been thinking about for awhile and well... It was iconic. Why should all the mundanes get to try it out and not him? 

"Nevermind that. Are you ready? The night waits for no man, not even for one as gorgeous as myself!" Magnus twirled his fingers, sending the Chairman back home for the evening and hooking a hand around his dear cabbage's arm. Ragnor slung his coat over one arm.

"Let's just get this awful event over with, shall we?" Ragnor huffed once more.

"That's the spirit." Magnus quipped before opening a portal; transporting himself, his green companion and a large blue box through it. 


	5. Let the Festivities Begin

**Summary for the Chapter:**

> Alec kind of likes his costume... Maybe. But that doesn't mean he likes the party. Especially when he's reminded that his pop culture references need work. 
> 
> And where is Magnus?

Music pumped through the speakers on an almost ear splitting level. The atmosphere was lively, costumed individuals already writhing on the dance floor. If there were any place to be for a Halloween party, Pandemonium was the place. And Alec was already feeling uncomfortable. 

He steadied his hand on the plastic weapon strapped to his side as if it could replace the power in his stele or the dangerousness of his bow. For all the absurdity of dressing in a costume he had to admit... He kind of liked how the clothes fit him. He had borrowed black boots from Magnus and stuffed the ends of his pants into them and the vest was snug against his chest. 

He also had to admit... He was looking forward to seeing just how Magnus would look tonight.

"Alec!" Izzy screamed from the side of the room. She was smiling, standing next to someone Alec didn't immediately recognize who wore a dark leather jacket. Then the person turned and Alec stifled a groan. Simon waved in greeting.

"Er... Yeah, I still have no idea who you are." Alec admitted, glancing from his now laughing sister to the mundane-turned-vampire. 

Izzy twirled in her long skirt and her blond wig whirled right along with her. Alec had never seen his sister so covered up for a party. Her arms were covered in a sweater that had a large "R" stitched into it. Izzy tossed blond hair over one shoulder and hooked a finger at him.

"That's what you get for not watching movies with us." She accused.

"How can you not have seen Grease?!" Simon exclaimed. Alec squinted at him and silently reminded himself that fighting with the vampire would be greatly discouraged by his boyfriend. 

"Some of us have lives." He grumbled. 

"Well, Simon and I are characters from that movie!" Izzy explained, hooking an arm around Simon. 

"And Iz was explicitly instructed to be Sandy from the earlier part of the movie cuz... well... she always looks like badass Sandy from the end." Simon blushed, ducking his head when Izzy turned a dazzling smile at him. 

"Yeah, still don't know what you're talking about... Have you guys seen Jace?" Alec glanced around the dance floor seeking out his parabatai. He needed to be around someone a little more normal.

Izzy shrugged and gestured toward the bar. 

"He's probably brooding somewhere over there. Clary hasn't shown up yet." 

"Um... Alec?" Simon's voice halted him. Alec turned back to the annoying vampire who was studying his costume.

"What?" Alec grumbled, keen to be rid of him already.

"Do you know who you're supposed to be?" Simon asked, smirking at him. 

Alec felt a flush creeping up his neck. He had a feeling he knew where this was going. He nodded in response.

"And is... Magnus going to... Er... Match you?" Simon could barely contain his laughter now. 

Alec glowered at him.

"Y'know Simon, I don't need magic for you to be afraid of me. Undead or not." Alec crossed his arms and took a step toward the vampire who immediately shut up, his Adam's apple visibly bobbing when Simon swallowed nervously. 

"C'mon, Simon." Izzy laughed, pulling her boyfriend toward the dance floor.

Alec watched them leave for a second before turning his attention toward finding his parabatai. He really hated parties.

 

\--

 

"You should try the punch." Jace said with an uncharacteristically deep voice. Alec glanced at his parabatai, eyebrow raised. He knew what Jace was dressed as effect was still funny.

Jace had taken the mask off to take a swig of an orange cocktail. Alec was used to seeing his blood brother in black leather but the bulky armor was something new. He was covered in it and an equally black cape trailed after him as he walked. Jace was loving it. He always fancied himself a superhero and tonight, he was one. It was something small Alec was secretly grateful to Magnus for. 

"Using that deep voice is gonna strain your throat." Alec retorted. He eyed the cocktail in Jaces hand. It probably wasn't best to drink anything unless Magnus offered it to him. He wasn't the biggest fan of alcohol anyway and he had seen pixies near the bar before he joined Jace. 

"I have to do this." Jace countered. "I'm Batman."

Jace offered him the goofiest smile Alec had ever seen and again, Alec was secretly grateful. He shrugged, eyes roaming the room. The party had been in full swing for a half hour and the guest of honor had yet to show. Alec was beginning to fidget. 

Jace most have sensed his unease and threw an arm around him. The cape suddenly swished against Alec's back engulfing the two of them for a moment.

"Don't worry, he probably just wants to make a grand entrance." Jace reassured.

And almost like magic (probably _actually_ by magic) there was a loud booming sound and the room suddenly filled with fog. The dancing halted as everyone turned toward the sound. Alec craned his neck to get a glimpse of the large doors at the end of the floor. This was typical Magnus  turning up late to his own party so everyone would focus on him.

Alec sighed. He loved the Warlock, he just had to remember that. 

Jace dug his elbow into Alec's side. Sudden trepidation filled Alec as the doors burst open and the music blared again. More fog poured in and in came men carrying a large reclining throne. Atop the throne leaned none other than Alec's boyfriend, bathing in the attention of all his guests.

Alec groaned. He couldn't fully see the costume Magnus was wearing but he knew what it would be. How else would he be dressed sitting atop a throne carried by guys in skimpy costumes?

This night was his personal torture. 

 


	6. Admiring the Costumed Effect

**Summary for the Chapter:**

> Magnus is just having a grand ole time...

It was perfection. Sheer, unadulterated perfection. And Magnus was reveling in every second of it.

The men carrying his gilt throne were werewolves he had picked from his Halloween show auditions. They were dancers from a show off Broadway and the small fortune to have them carry him into the party was well worth it. The view was spectacular because the instant he had entered the room, his eyes had found Alec. 

It was magic of a different kind, the attraction that pulled his eyes directly to the Shadowhunter. Magnus's eyes almost slipped to their cat form with anticipation of Alexander seeing him. This was all for him. The party, the costumes, the entrance... All of it was an exclaimation of how Alec made Magnus want to celebrate every moment of their lives together.

Every party was an excuse to dance with Alexander. Every event was a reason to hold his hand in public. Every date was an occasion to show off his boyfriend to the world. And this was no different.

Magnus had chosen the costumes with care. His own was barely a costume at all. His torso was bare, showing off every inch of muscle that was only to be touched by one person. On his hips, Magnus wore gold chains that rested against red cloth that flowed to his feet. Outside of pop culture, he looked like an Egyptian rarity. But in today's age, it was a popular costume from Star Wars. With his own minor alterations. 

Magnus gestured for the wolves to lower his throne. The music was sweeping through the crowd and the guests cheered as sudden black balloons burst above their heads, showering everyone with glitter. He grinned watching Alec across the room shaking glitter out of his hair. 

Magnus took his time, moving through the dancing crowd. He wanted to lengthen the moment. He could feel Alec trying to track his movements. Bodies moved around him but he couldn't be bothered by it. The chains pulled across his hips with every step. The heat was palpable and Magnus was glad he had foregone anything on his upper half. He let a smile spread against his lips as he neared the bar which his boyfriend hadn't moved from.

Alec was watching him with intensity. His eyes didn't stray downward to take in all of Magnus's barely there costume, they held his gaze. Magnus watched as Jace shifted awkwardly beside his parabatai, elbowing Alec in the side but his archer didn't take the hint. Alexander kept his eyes on Magnus and in those few seconds before Magnus reached the bar he could swear everything else fell away. There was only the two of them.

"Alexander," Magnus purred, a smile tugging at his lips. 

Alec was still staring at him, his eyebrows knit in concentration. Magnus let his eyes travel up and down Alec's body, scanning the costume he had deemed worthy of the archer. The vest hugged Alec's chest and the white shirt underneath practically stretched over his muscles. A wide weapons belt was slung low on his hips and if Magnus had to bet on it, he was sure the pants would ececenutate every curve of Alec's ass in the best of ways. He mentally patted himself on the back for the excellent choice. 

"Darling? Are you having a good time?" Magnus teased, moving closer to Alec until he was just a hands width away. He settled his hands on his hips, knowing the action would cause his biceps to buldge just a bit and also knowing that it would drive Alec crazy.

He watched Alec take a deep breath before his eyes finally trailed down Magnus's body. Another mental pat on the back. When Alec pulled his gaze back up to Magnus's face the intensity was still there accompanied by the most endearing blush.

"Magnus..." Alec said slowly as if he were deflating. He tentatively reached a hand out and his fingertip grazed the chain just above Magnus's hip bone.

A shiver ran through Magnus. This was what Magnus had been wanting. This is what he had spent weeks planning this party for; he had wanted a stunned Alec. And that was exactly what Magnus had gotten.

"Yes, Alexander?" He purred again. Alec was sweeping his finger slowly across Magnus's hip, following the chain with his eyes. Magnus silently thanked the gods for the chosen costume. 

Alec's eyes flickered back to his. God, he looked so gone. 

"I..." Alec just couldn't seem to get an actual sentence out of his mouth. Not that Magnus was really complaining.

"Magnus!" Came a voice behind him. Alec jumped almost violently away from Magnus and the warlock cursed every breath Raphael would take for the rest of his undead life. 

He turned slowly to glare at the unwelcome intrusion. Raphael was glowering right back at him, arms crossed against his chest.

"What is the point of throwing a party and being almost 45 minutes late!" Raphael demanded.

"It's called making an entrance, my dear Raphael." Magnus spit back. He turned back to Alec who it seemed was having a terrible time breathing properly. Alec's face was a bright shade of red and his gaze was fixed past Magnus's shoulder. 

"Alexander, we should probably make the rounds. Don't you think?" He teased, sliding his hand up Alec's arm. 

Alec nodded but made no move to peel himself away from the bar. Magnus squeezed his arm gently, searching his face for a break in the intensity. Alec's eyes flicked down to Magnus's lips. 

The next thing Magnus knew was that he couldn't breathe. Alec had pulled him forward so quickly that he hadn't had time to prepare himself for being kissed. Alec was sucking the air right out of his lungs, clamining all of Magnus's unspoken words. His hands gripped Alec's shoulders simply so that he could hold on. Alec's arms wrapped around him, caging Magnus in a strong embrace. In the next seconds, Magnus was grateful for those strong arms around him as Alec slipped his tongue into Magnus's mouth and all the strength left Magnus's legs. 

This had been an excellent costume choice indeed! 


	7. Halloween Isn't So Bad

**Summary for the Chapter:**

> Magnus explains his choices and Alec learns to appreciate the holiday.

Alec couldn't breathe.

And that probably had a lot to do with the fact that Magnus was kissing him back as ferociously as he had initially. The costume was too perfect. There was barely anything to it! But Alec couldn't get the image of Magnus riding into the room on a throne out of his head. He looked like an ancient God sculpted from bronze and gold. And Alec had to touch him to know he was real.

But touching wasn't enough. 

Alec had tried to mentally prepare himself for this probable outcome. He had seen the costume options online; he knew what Magnus could choose. But it **didn't** prepare him. He didn't realize how badly the costume would make him want to touch Magnus. He couldn't guess how the chains wrapped around his waist would make him feel- desparate to trace them and even more desparate to be rid of them! 

Alec gripped Magnus's golden sides, anchoring the warlock to him. But it wasn't enough.

"I told him not to pick this one." Ragnor's voice was suddenly very loud in his ear.

Alec shoved himself back but kept his hands on Magnus. He was having trouble catching his breath and was sure his face looked as wild as his mind was. One glance at Magnus told him his boyfriend seemed to be having the same issue. 

"Honestly Magnus, the shock could have killed the boy." Ragnor tittered. 

Magnus regained his composure much faster than Alec did.

"No one understands the importance of a grand entrance." Magnus huffed at Ragnor. But Alec could not have disagreed more. 

Magnus ran a hand up and down Alec's arm as he spoke. The action calmed Alec some but made other parts of him simply _ache_.

"Where did you leave your box?" Magnus asked, turning a little sideways to speak to his friend.

Ragnor was dressed in costume as well but Alec couldn't have guessed what this one was either. He wore a white shirt and pants with suspenders complete with a bow tie. A tweed jacket hung from his arm. Alec really needed to watch more tv it seemed.

"Oh it's somewhere in this room. Some of the young ones kept trying to sneak into it while it was in the hall. It's not exactly large enough to do anything properly in it though is it?" Ragnor waved his hand toward something that looked like a phone booth painted blue. Magnus laughed.

"I thought it was supposed to be bigger on the inside?" Magnus's fingers played with Alec's sleeve absentmindedly.

"Well it certainly isn't big enough for anything you'd want to do."

Alec felt the heat surge into his cheeks again as Ragnor looked pointedly at the two of them. Ragnor snickered.

"Have you seen Catarina?" Ragnor asked, sweeping his eyes around the room.

It was then Alec remembered that they were in fact still at the club in the middle of a party. He could see Izzy and Simon dancing in the crowd and he wasn't sure but he thought he could see Raphael standing a little off from them keeping a close eye on Simon. He searched the room for his parabatai but almost missed him. Alec had assumed he would find him dancing with Clary when in fact he was standing off to the side having what seemed an animated conversation with someone with very black hair. 

"I've not really taken notice of anyone, dear Doctor. But she may have glamored herself to look like your companion instead of finding the appropriate costume. My advice is look for someone with unruly blond hair." Magnus laughed again, turning his attention back to Alec.

Ragnor left them, making a noise of disgust before he went. Embarrassment swept through Alec. Was he really being that transparent with his thoughts?

"Would you like to continue where we left off?" Magnus teased, moving a little closer back to Alec.

This time Alec smiled at him. Perhaps now wasn't the time to try and rip Magnus's costume off but later... Later was a different story. For now, he had to be a good sport about the party. Magnus was enjoying himself and Alec didn't want to be a buzz kill. He cleared his throat.

"Tell me who everyone is supposed to be." 

Magnus smiled and shifted so they were both leaning against the bar surveying the crowd. He gestured toward the blue box that Alec couldn't understand the purpose of.

"Ragnor has always had a love of science fiction. Awhile back, he discovered this show about a time traveling doctor who helped different species. He fell in love with the idea. So he's dressed as the Doctor and Catarina is his companion. Well, technically Catarina is dressed as the Doctor's wife but same difference." 

Alec could feel his face pulling in confusion.

"Why does he need a phone booth? Does he heal people when they're inside of it?" He questioned. The whole idea seemed ridiculous.

Magnus let out a barking laugh. 

"Remind me to find some reruns for you later. Then it will make more sense!" He waved a hand at the dancing Izzy. "Your lovely sister didn't explain what she was?"

"She mentioned something about grease?" Alec was truly clueless about the whole thing. Magnus slid an arm around him to pull him a little closer.

"She's a character from a musical about a good girl who falls for a bad guy. That's who Simon is supposed to be. I thought it would be funny to play to their opposition. They seem to be enjoying themselves."

And it was true, Izzy had the biggest smile on her face as Simon twirled her around the dance floor. But Alec could still see Raphael watching them from farther away. 

"And who is Raphael supposed to be?" Alec could only see that the vampire was wearing dark clothes and a shockingly pink jacket. He wasn't sure how Magnus had managed to convince him to wear it to be honest. 

"Oh... Well that costume is apart of the movie as well." Magnus chuckled. "There's this other character who likes the main bad guy and well... I thought it was humorous. Besides, Raphael looks great in bubblegum pink!"

Magnus's whole body shook with laughter as Simon suddenly pulled Raphael into a dance. Alec smiled at how they all seemed to be having fun. He glanced back to his parabatai who was pulling the black haired girl onto the dance floor.

"Okay, I know who Jace is dressed as." 

"Yes, I thought that was a little hitting the nail on the head. And I'm glad you already know who he is 'cuz I don't think I'd be able to adequately explain Batman... Clary looks good in her costume too." Magnus nodded at the crowd.

"Clary?" Alec couldn't remember seeing her since the party started. And there was no way Jace would abandon his search for her. He stared a little harder at the female Jace was dancing with.

"Wonder Woman," Magnus explained. And then the female turned and recognition hit Alec.

Clary looked completely different with the black hair. And her costume was the shortest of everyone's there. Jace sported a goofy grin as he danced next to her. Alec grinned right along with him.

"Y'know, as much as I hate Halloween, the costumes were a good idea. Everyone looks great." Alec admitted. Magnus squeezed his shoulder.

"Especially you," he smiled at Magnus who practically lit up at the compliment. 

Alecs body was humming. He could feel tingles along his fingers and butterflies in his stomach as he looked again at Magnus. How did he ever get so lucky? 

"I'm glad you like it." Magnus brought his lips closer to Alec's. "Perhaps I'll keep it for future fun."

Alec grinned.

"Thatd be great." 

Maybe Halloween parties weren't that bad after all. 


End file.
